package 集合.set集合;

import java.util.HashSet;

public class HashSet02 {
    @SuppressWarnings({"all"})
    public static void main(String[] args) {
        HashSet hashSet = new HashSet();
        for (int i = 0; i < 12; i++) {
            hashSet.add(new Book(i));
        }
    }
}
class Book{
    private int n;

    public Book(int n) {
        this.n = n;
    }


    @Override
    public int hashCode() {
        return 100;
    }
}
